Method of making dental pins



Aug. 2, 1932. K. K. LEDIG 1,869,817

METHOD OF MAKING DENTAL PINS Fil ed Aug. 9. 1929 Patented Aug. 2, i932 STATES PATENT- OFFICE KURT K. LEDIG, F NEWA IRK, NEW' JERSEY, ASfiIGNOB TO AMERICAN PLA woans. or NEWARK, new JERSEY,

A COBQOBATION OF NEW: JERSEY mnrnon OF MAKING ram-ran rs Application filed August 9,

This invention relates to dental pins used for holding teeth to gold or similar plates, and more particularly to a method of making such pins.

Dental pins of the type herein disclosed are necessarily small, seldom exceeding 4" in length and in diameter, and due to their size, they have heretofore been cut from nickel Wire upon which gold has been depositb'? ed by plating or rolling. However, pins made in accordance withsuch a method are objectionable as the points at which each pin is cut from the wire is not covered with gold with the result that small nickel surfaces are exposed to the corroding action of mouth acids.

It is an object of thisinvention to provide a method of making a dental pin by whichno nickel surfaces are exposed to the corroding and dangerous action of mouth acids.

This and other objects are accomplished by the novel treatment of the metals employed as hereinafter described and claimed. In order to assist in the explanation of the method, the accompanying drawing is provided,in which:

Figure 1 is a sectional view of a dental pin made in accordance with my invention whereby the nickel base is completely covered so that no nickel surfaces are exposed.

Figure 2 is a sectional view showing the manner in which nickel surfaces are exposed on pins made in accordance with methods heretofore employed.

Referring to the drawing, in Figure 2, is shown a dental pin made in accordance with heretofore well known methods, in which a nickel base is covered with'a goldplate 4. Thepin is cut from nickel wire upon which the gold has been deposited 'by plating or rolling, and as isshown in the drawing, the points at which the wire is cut leave on each pin, at the top and at the bottom, the areas 5 and 6, which are not covered by the gold 1929. 1 Serial Ho. $84,741.

plate. The areas 5 and 6, being of nickel base 3, are attacked by the mouth acids.

In practicing my invention, the pins are first cut from a nickel wire and then plated with gold to produce a pin such as shown in Figure 1, having a base '7 of nickel, completely covered with a gold plate 8, and then the gold covered nickel base is heated in an electric furnace in proximity to-a suitable reducing agent, such as charcoal, and the'temperature of the furnace is raised to approximately 7 degrees centigrade, or at other temperatures depending upon the plating material employed, the temperature of the furnace being below the melting temperatures of the metals used.

The pin is allowed to remain in the'furnace for approximately'twenty minutes until the gold has been thoroughly difiused with the nickel base, so that an efiective alloy is produced, at the junction of the nickel base and the gold plate.

While in the electric furnace under heat, the nickel base is protected from oxidation by the reducing agent, the latter also serving to destroy any minute coating of oxides which may be upon the surface of the base.

It should be noted that other reducing means besides charcoal and the electric furnace may be employed; for example, a diffusion of the plate into the metal of the pin may be accomplished by beating them in hydrogen gas. If the nickel bases are already free from oxide when placed into the furnace, a difiusion of the gold into the metal of the pin may be accomplished in a vacuum or in any inert gas, the essential point being the prevention of oxidation during the heating process.

A dental pin made in accordance with my method will have ametallic base completely covered with a gold plate firmly adhering thereto, and presenting no surfaces of the base metal exposed to the destructive acids of the mouth.

From the above description it will be seen that I have provided an efiective and simple method of making satisfactory dental plus which are not effected by the mouth acids.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

The method of making a dental pin having a nickel base, comprisi plating the pin with gold then heating the p ated pin in a furnace containing charcoal at a temperature below the melting points of the metals used, to cause a difl'usion of the gold plate with the nickel base, the gold plate completely covering the This specification signed this 24th day of July, 1929.

KURT K. LEDIG. 

